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81.
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Variation in levels of phenolic acids and flavonoids in Scrophularia striata Boiss. cells cultured in both shake flask and bioreactor in vitro systems, was studied at different growth phases. Four phenolic acids (cinnamic, salicylic, coumaric, and caffeic acid), one stilbenoid (resveratrol), and seven flavonoids (diosmin, rutin, kaempferol, catechin, myricetin, quercetin, and luteolin) were analyzed by high-performance liquid chromatography with photodiode array detection. Production of phenolics in the bioreactor was higher than in shake flasks. Catechin was the most abundant flavonoid in both culture systems, while quercetin, which was detected only in the bioreactor, was the lowest amount represented (32.82 μg g?1 DW). Resveratrol accumulation in bioreactor cultures was 59.84-fold higher than that in shake flasks. Moreover, hierarchical clustering analysis based on Pearson’s correlation coefficient confirmed a positive correlation between the growth phase and some metabolites. The flavonoid accumulation increased with the cells’ physiological age in the bioreactor. Principal component analysis showed that the time course of induction of phenolic acids, flavonoids, and a stilbenoid (resveratrol) was significantly correlated. These findings highlight the capacity of S. striata for large-scale production of desired phenolics using a bioreactor system.  相似文献   
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84.
The presence of fluoride in drinking water can be either beneficial or harmful for human health, depending on its concentration. Most adverse effects of fluoride are observed at high concentrations (above 1.5 mg/L). This study was aimed to evaluate the effect of fluoride concentrations in drinking water on spontaneous abortion in two regions: one with low fluoride concentration and another with high fluoride concentration. The results showed that there is a relationship between the concentration of fluoride in drinking water and abortion, so that the risk of abortion increased at high concentrations of fluoride. However, further studies are needed to clarify this relationship due to the small area and population in this study.  相似文献   
85.
Increasing insecticide resistance requires strategies to prolong the use of highly effective vector control compounds. The use of combinations of insecticides with other insecticides and phytochemicals is one such strategy that is suitable for mosquito control. In bioassays with Aedes aegypti and Culex annulirostris mosquitoes, binary mixtures of phytochemicals with or without synthetic insecticides produced promising results when each was applied at a LC25 dose. All mixtures resulted in 100% mortality against Cx. annulirostris larvae within 24 h rather than the expected mortality of 50%. All mixtures acted synergistically against Ae. aegypti larvae within the first 24 h except for one mixture that showed an additive effect. We conclude that mixtures are more effective than insecticides or phytochemicals alone and that they enable a reduced dose to be applied for vector control potentially leading to improved resistance management and reduced costs.  相似文献   
86.
Cloud computing environments (CCEs) are expected to deliver their services with qualities in service level agreements. On the other hand, they typically employ virtualization technology to consolidate multiple workloads on the same physical machine, thereby enhancing the overall utilization of physical resources. Most existing virtualization technologies are, however, unaware of their delivered quality of services (QoS). For example, the Xen hypervisor merely focuses on fair sharing of processor resources. We believe that CCEs have got married with traditional virtualization technologies without many traits in common. To bridge the gap between these two technologies, we have designed and implemented Kani, a QoS-aware hypervisor-level scheduler. Kani dynamically monitors the quality of delivered services to quantify the deviation between desired and delivered levels of QoS. Using this information, Kani determines how to allocate processor resources among running VMs so as to meet the expected QoS. Our evaluations of Kani scheduler prototype in Xen show that Kani outperforms the default Xen scheduler namely the Credit scheduler. For example, Kani reduces the average response time to requests to an Apache web server by up to \(93.6\,\%\); improves its throughput by up to \(97.9\,\%\); and mitigates the call setup time of an Asterisk media server by up to \(96.6\,\%\).  相似文献   
87.
Head blight caused by Fusarium graminearum (F. graminearum) is one of the major threats to wheat and barley around the world. The importance of this disease is due to a reduction in both grain yield and quality in infected plants. Currently, there is limited knowledge about the physiological mechanisms involved in plant resistance against this pathogen. To reveal the physiological mechanisms underlying the resistance to F. graminearum, spikes of resistant (Sumai3) and susceptible (Falat) wheat cultivars were analyzed 4 days after inoculation, as the first symptoms of pathogen infection appeared. F. graminearum inoculation resulted in a greater induction level and activity of salicylic acid (SA), callose, phenolic compounds, peroxidase, phenylalanine ammonia lyase (PAL), and polyphenol oxidase in resistant versus susceptible cultivars. Soil drench application to spikes of SA, 24 h before inoculation with F. graminearum alleviated Fusarium head blight symptoms in both resistant and susceptible cultivars. SA treated plants showed a significant increment in hydrogen peroxide (H2O2) production, lipid peroxidation, SA, and callose content. SA-induced H2O2 level seems to be related to increased superoxide dismutase and decreased catalase activities. In addition, real-time quantitative PCR analysis showed that SA pretreatment induced expression of PAL genes in both infected and non-infected head tissues of the susceptible and resistant cultivars. Our data showed that soil drench application of SA activates antioxidant defense responses and may subsequently induce systemic acquired resistance, which may contribute to the resistance against F. graminearum. These results provide novel insights about the physiological and molecular role of SA in plant resistance against hemi-biotrophic pathogen infection.  相似文献   
88.
Parkinson’s disease (PD) is a progressive neurodegenerative disease characterized by progressive and selective death of midbrain dopaminergic neurons. Pharmacologic treatment of PD can be divided into symptomatic and neuroprotective therapies.  相似文献   
89.
International Journal of Peptide Research and Therapeutics - The aim of this experiment was to evaluate the effects of bioactive peptides derived from sesame meal (BPSM) compared with...  相似文献   
90.
Neurodegenerative disorders are mainly associated with amyloid fibril formation of different proteins. Stem bromelain (SB), a cysteine protease, is known to exist as a molten globule state at pH 10.0. It passes through the identical surrounding (pH 10.0) in the gut epithelium of intestine upon oral administration. Protein–surfactant complexes are widely employed as drug carriers, so the nature of surfactant toward protein is of great interest. The present work describes the effect of cationic surfactants (CTAB & DTAB) and their hydrophobic behavior toward amyloidogenesis behavior of SB at pH 10.0. Multiple approaches including light scattering, far UV-CD, turbidity measurements, and dye binding assay (ThT, Congo red and ANS) were performed to measure the aggregation propensity of SB. Further, we monitored the hydrodynamic radii of aggregates formed using dynamic light scattering technique. Structure of fibrils was also visualized through fluorescence microscopy as well as TEM. At pH 10.0, low concentration of CTAB (0–200 μM) induced amyloid formation in SB as evident from a prominent increase in turbidity and light scattering, gain in β-sheet content, and enhanced ThT fluorescence intensity. However, further increase in CTAB concentration suppressed the fibrillation phenomenon. In contrast, DTAB did not induce fibril formation at any concentration used (0–500 μM) due to lower hydrophobicity. Net negative charge developed on protein at high pH (10.0) might have facilitated amyloid formation at low concentration of cationic surfactant (CTAB) due to electrostatic and hydrophobic interactions.  相似文献   
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